Railway signaling system.



LQSLU.

FIGHE H. A. WALLACE.

RAILWAY SIGNALING SYSTEM.

APPucATloN FILED Nov. 8. 1913.

Patented June 26, 1917.

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INVENTUM Q//a/a Patented J une H. A. WALLACE.

RAILWAY SIGNALING SYSTEM.

APPLICATION FILED Nov. 8. 1913.

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HERBERT A. WALLACE, OF NEW YORK, N.

Y., ASSIGNOR TO THE UNION SWITCH 85 SIGNAL COMPANY, OF SWISSVALE, PENNSYLVANIA, A CORPORATION OF PENNSYL- VANIA.

RAILWAY SIGNALIN G SYSTEM.

LQSLMCO.

Continuation of application Serial No. 498,883, led May 28, 1909.

Specification of Letters Patent.

Patented J une 26, i917.

This application led November 8, 1913.

Serial N0. 799,911.

To all 'whom t may concern.'

Be it known that I, I-Innnn'r A. IALLAGE, a citizen of the United States, residing at New York city, in the county of New York and State of New York, have invented certain new and useful Improvements in Railway Signaling Systems, of which the following is a specication.

My invention relates to railway signaling systems, and particularly to systems in which the signals are controlled by track circuits. An object. of my invention is to control a given number and arrangement of signals with the fewest number of track cir-cuits.

The present application is a continuation of my pending application, Serial No. 498,883, filed May 28, 1909, for railway signaling systems, so far as the subject-inattcr common to the two is concerned.

I will describe several forms of signaling systems embodying my invention, and will then point out the novel features thereof in claims.

In the accompanying drawings, Figure 1 is a diagrammatic view showing a stretch of railway track over which cars or trains usually travel in only one direction, and having applied thereto one form of signaling system embodying my invention. The signaling system illustrated embodies home and distant signals, the home signal and distant signal being on diferent posts. Fig. 2 is a view showing a modification of my invention, the home signal anddistant signal being located on the same post. Fig. 3 is a view showing my invention applied to an overlap system of signaling. Fig. e is a diagrammatic view illustrating a stretch of railway track over which cars or trains travel in both directions and having applied thereto a signaling system embodying my invention.

Similar reference characters designate corresponding parts in each of the several views. Referring to Figs. l, 2 and 3 of the drawings, A designates a stretch of railway track over which traiiic moves in the direction indicated by the arrow, which'stretch is divided by insultions c to form track sections B, (l, D, etc.

Each track section is provided with a track circuit comprising the rails of the section, two relays R and It connected with the rails adjacent the ends of the section respectively, and a source of alternating signaling current connected with the rails` adjacent the middle of the section. As here shown, this source of current is a transformer T2 whose secondary is connected with the rails of the track section and whose primary is connected with mains f to which alternating signaling current is supplied from a source F. The track relays are preferably of a type which will respond to the alternating signaling current but not to direct current, and in the drawings this is indicated in the conventional manner by diagonal lines in the relays.

IVith an arrangement of track circuit such as I have just described, that is, with the source of signaling current connected at about the middle of the track circuit and a relay at each end thereof, I have observed in practice that as a car or train enters one end of the track circuit it will open the track relay adjacent that end only, and that the track relay at the other end of the track circuit is opened only when the car or train has approached to within approximately 50 or 100` feet of the point of connection of the signaling current with the track rails. Also, after the car or train has passed about the same distance beyond this point of connection, the relay first opened again closes, the relay at the exit end remaining open how-` -ever until after the car or train leaves the track circuit. In this invention I have taken advantage of the foregoing facts by arranging one or more railway signals to be controlled by the relays as hereinafter explained.

Referring now particularly to Fig. l, a home signal S is located adjacent the en-` trance end of each track section and is controlled by both track relays R and R for such section. Each track section, therefore, constitutes a block in this particular embodiment of my invention. The circuit for signal S at the entrance end of track section I) is from battery l0 through contact il of relay R, wire 12, contact 2l of relay R, signal S, wires 22, 23 and 24: to battery 10. The circuits for the other signals S are similar to that just traced. I also place in each track section a distant signal S which signal is located adjacent the point at which a car or train moving through the section in the direction of the arrow opens the track `relay 'It' at the exit end of the section.

Each distant signal S is controlled by the track relay R at the exit end of the same section and also by a circuit controller 13 operated by the home signal S for the section next in advance. For example, the circuit for signal S in track section D is from battery 10, through contact 25 of relay R, wire 13, circuit controller 13 operated by signal S, wire 19, signal S, wires 20, 23 and 24 to battery 10. rlhe circuit for the distant signal S for section C is similar to that just traced. It is evident that with this arrangement, each distant signal S will change to caution position at approximately' the time it is passed by a car or train. The point at which a car or train moving through a track section will cause the track relay at the exit end of the section to open is somewhat variable due to conditions of the trackway as to moisture, etc., and in order to prevent a distant signal from moving to caution position before it is reached by an approaching train the signal should be located at least as far in the rear of the point of connection of the transformer with the track as the extreme position in the rear of that point at which a car or train will under any circumstances cause the relay at the exit end of the section to open. ln accordance with the usual practice, the signal is preferably located even a short distance in the rear of this extreme position, so that the signal does not change until after it has been passed by the front end of a car or train. rlhis location of the signal is indicated on the drawing, in which the point designated as the point at which relay R opens7 is the average location of this point.

It will be evident that with this arrangement of control, each distant signal S will indicate the condition of the next succeedingl track section as regards occupancy by a car or train, and that each distant signal will move to the caution position at substantially the time it is passed by a car or train, due to the fact that at such times the car or train opens the relay R at the exit end of the track section. Also when a car or train approaches a track section the home signal S of which is in danger position, it may proceed into the track section at low speed, and, if it finds the distant signal S in such track section in the clear position, it may proceed at full speed, knowing that the next succeeding block section is` unoccupied.

An arrangement such as I have shown in Fig. 1 is particularly applicable to a signaling system in which the home signals are spaced at distances of from 500 feet to two miles or ymore, apart, in which systems it is desirable to locate the distant signals less than a block section in the rear of the home signals whose indications they repeat. Heretofore such an arrangement of signals has required the use of two or more insulated track sections between each two home signals, in order that the distant signals may be moved to caution position as soon as they are passed by a car 0r train. In my invention only one track section is required to perform this function.

Referring now to Fig. 2, in the arrangement here shown each tracksection is employed for two block sections by placing a home signal S and a distant signal S adjacent the entrance end of each track section, and another home signal S2 and a distant signal S3 adjacent the point at which the relay lt at the exit end of the same track section is opened by a car or train moving through the section. The locationmof these signals S2 and S3 with respect to the point at which relay R opens is preferably the same as the location of signal S in Fig. 1 hereinbefore explained. Each home signal S is controlled by the relay R at the entrance end of the corresponding track section, and each home signal S2 is controlled by the relay R at the exit end of the corresponding track section. Each distant signal S is controlled 'by a circuit controller 111 operatively connected with the adjacent home signal S, and also by a circuit controller 15 operatively connected with the next succeeding home signal S2. Each distant signal S3 is similarly controlled by a circuit controller 16 operatively connected with the adjacent home signal S2 and also by a circuit controller 17 operatively connected with the next succeeding home signal S. For example, the circuit for home signal S at the entrance end of track section D is from battery 26, through contact 27 of relay R, wire 28` signal S, wire 29 to battery 26. rlhe circuit for the. adjacent distant signal S is from battery 30, through wire 31, circuit controller 15 operated bysignal S2, wire 32, circuit controller 14 operated by signalS, distant signal S, wires 29, 33 and 37 to battery 30. rlhe circuit for home signal S2 in track section D is from battery 34:, through contact 35 of track relay R, wire 36, signal S2,

wires 37, as and as 'to baan-y ai. They arcuit for distant signal S3 in track section l) is from battery 34, through wire 39, circuit controller 17 operated by signal S, wire 40, circuit controller 16 operated by signal S2,

distant signal S3, wires 37, 33, and 33 to bat- The circuits for the signals for 1 tery 34. track section C are similar to those just traced.

lt will be seen. therefore, that as a car or train enters track section D, the home and distant signals S and S for that section will move to danger and caution respectively; as the car or train passes the point at which relay R opens, the home and distant signals S2 and S3 will move to danger and caution respectively; and as the car or train passes the point at which relay It again closes, the home signal S will move to clear position, but the distant signal S will remain in caution position as long as home signal S2 remains at danger. Then as the car Referring now to Fig. 3, I here show an overlap system of signaling, in which home signals only are used. A home signal S is placed in each track section adjacent the point at which a car or train moving through the track section opens the relay It at the eXit end of the track section. The location of each signal with respect to the point at which relay R of the same section opens is preferably the same as the location of signals S in Fig. l and hereinbefore explained. Each signal is arranged to be controlled by the relay It of its own track section and by both relays R and R of the track section next in advance. For example, the circuit for signal S in section E is from battery 4l through contact 42 of relay It', wire 43, contact 44 of relay R, contact 45 of relay It', wire 46, signal S, wires 47 and 48 to battery 41. The circuits for the other signals are similar. Asa car or train passes a signal S, this signal will move to danger position and will remain at danger until the car or train has passed out of the track section neXt in advance; and a car or train finding a signal in the clear position may approach the next signal at full speed, knowing that the track for some distance in advance of such second signal is unoccupied. In this modification of my invention, as well as in the preceding views, the number of track circuits required is half the usual number.

Referring now to Fig. 4, I here show my invention applied to a track section C over which traffic moves in both directions. As in the preceding views, the track section is provided with a transformer T2 connected with the track rails adjacent the middle of the section, and two relays R and It, one adjacent each end of the section. S designates a signal governing traffic in the direction of the arrow 49, which signal is located adjacent the point at which the relay R is opened by a car or train moving in the direction of arrow 49, and which signal is controlled by relay R. Another signal SL governing traflic in the direction of arrow 50 is located adjacent the pointat which relay R is opened by a car or train moving in such direction, and is controlled by relay R. The location of these signals with respect to the point at which the relay controlling them opens is preferably the same as the location of the signals S in Fig. l and hereinbefore explained. It is evident that a car or train entering the track section from section D will place signal SL in danger position and will hold it in such position until the car or train passes the signal; also that as the car or train passes signal S, this signal will change to danger and will remain at danger until the car or train leaves track section C. 'I'his embodiment of my invention provides a preliminary section extending from each signal S and SL to the adjacent end of the section C, and hence itis impossible to bring two cars or trains together in the space between the signals. A system of this type is particularly adapted for the protection of a single track through tunnels, over drawbridges, etc. In this embodiment of my i11- vention, I employ one track circuit to perform functions for which three track circuits have heretofore been required.

Although I have not herein shown or described any means for supplying motive power to the cars or trains traveling along the railway, it is understood that signaling systems embodying my invention are equally well adapted for use on railways using any form of motive power, such as on steam or electric railways or on railways using compressed air, storage batteries, etc. Nor do I wish to limit myself to alternating signaling current in the track circuits, for the reason that direct signaling current may be used instead, the arrangement of track relays, sources of signaling current and signals remaining the saine.`

Although I have herein shown and described only a few forms of signaling systems embodying my invention, it is understood that various changes and modifications may be made therein within the scope of the appended claims, without departing from the spirit and scope of my invention.

I-Iaving thus described my invention, what I claim is:

l. In a signaling system for railways, a section of track, a source of signaling current connected with the track rails adjacent the middle of the section, two track relays one connected withY the rails adjacent each end of the section, a signal located adjacent the entrance end of the section and controlled by the adjacent relay, and another signal located adjacent the point at which the relay at the exit end of the track circuit is opened by a car or train and controlled by said relay at the exit end of the track cir` cuit.

2. In a signaling system for railways, a section of track, a source of signaling current connected with the track rails adjacent the middle of the section, two track relays one connected with the rails adjacent each end of the section, a home signal located adjacent the entrance end of the section and controlled by the adjacent relay, a home signal located in advance of the track section, a circuit controller operated by the latter honie signal, and a distant signal located adjacent the point at which the relay at the exit end oi' the section is opened by a car or train passing through the section and controlled by said relay at the eXit end of the section and by the said circuit controller.

3. In a signaling system for railways, a plurality of successive track sections, a source of signaling current connected with the track rails of each section adjacent the middle of the section, two track relays for each section one connected with the.rails adjacent each end of the section, a home signal adjacent the entrance end of each section and controlled by the relay adjacent the entrance end of the section, a circuit controller operated by each home signal, a distant signal in each tracksection and located adjacent the point at which the relay at the exit end of the corresponding track section is opened by a car or train passing through the section, each distant signal being controlled by the relay adjacent the exit end of the corresponding track section and by the circuit controller operated by the home signal for the track section neXt in advance.

4:. In a signaling system for railways, a plurality of successive track circuits each formed in part by the track rails of the railway, a source of signaling current connected with the track rails of each track circuitv adjacent the middle of the track circuit, two relays for each track circuit one connected with the rails adjacent each end of the circuit, a signal for each track circuit each signal being located adjacent the point at which the relay at the exit end of the corresponding track circuit is opened by a car or train passing over the track circuit, and each signal being controlled by the relay at the exit end of the corresponding track circuit and by both of the relays for the track circuit neXt in advance.

5. In a railway signaling system, a plurality of successive track sections; a source of signaling current for each track circuit and connected with the track rails adjacent the middle of the section, two relays for each section one connected with therails adjacent each end of the section; a signal for each section each located adjacent the point at which the relay at the exit end of the corresponding section is opened by a car or train, each signal being controlled by the relay at the exit end of the correspending section and by the relay at the entrance end of the section next in advance.

6. In railway signaling, a track,circuit, a source of signaling current connected therewith adjacent the middle of the track circuit, two relays one connected with the rails adjacent each end of the track circuit, a signal located adjacent the entrance end of the track circuit and controlled by the relay adjacent that end, and a second signal located adjacent the point at which the relay at the exit end is opened byV a car or train passing through the track circuit and controlled by the last-mentioned relay.

7. In railway signaling, a track circuit, a source of signaling current connected with the rails of 'the track circuit adjacent the middleV of thel circuit, two relays one connected with the rails adjacent each end of the track circuit, a signal located adjacent one end of the track circuit and controlled by the relay adjacent that end, and a second signal located between the last-mentioned end and the point of connection of the source with the track circuit and controlled by the relay at the other end of the track circuit.

S. In combination, a section of railway track, a source of signaling current connected with the track rails adjacent the iniddle of the section, two track relays one connected with the track rails adjacent each end of the section, and a signal located adjacent the point farthest in the rear of the connection of the saidV source at which the relay at the exit end is ever opened by a car or train passing through thev section, said signal beingcontrolled Aby said relay at the exit end of the section.

f). In combination, a section of railway track, a source of signaling current connected with the track rails adjacent the middle of the section, twotrack relays one connected with the track rails adjacent each end of the section, and a signal located a short distance in the rear of the point farthest in the rear of the connection of said source at which the relay at the exit end is ever opened by a car or train vpassing through the section, said signal being controlled by said relay at the exit end o'l' the section.

10. In combination, a section of railway track, a source ot signaling current connected with the track rails adjacent the middle oi' the section, a track relay connected with the track rails adjacent the eXit end of the section, and a signal controlled by said relay and located adjacent the point farthest in the. rear of the point of connection of the said source at which the said relay is ever opened by a car or train passing through the section.

11. In combination, a section of railway track, a source of signaling current conand located a short distance in the rear of the point farthest in the rear of the connection of said source at which the said relay is ever opened by a car or train passing through the section.

l2. In combination, a plurality of successive sections of railway track, a source of signaling current for each section and connected with the rails adjacent the middle of the section, two relays for each section one connected with the rails adjacent each end of the section, a signal in each section and located adjacent the point farthest in the rearof the said connection of the source at which the relay at the eXit end of the section is ever opened by a car or train passing through the section, each signal being controlled by the relay at the eXit end of the corresponding section and by the relay at the entrance end of'the section next in advance.

13. In combination, a plurality of successive sections of railway track, a source of signaling current for each section and c011- nected with the rails adjacent the middle of the section, two relays for each section one connected with the rails adjacent each end of the section, a signal in each section and located a short distance in the rear of the point farthest in the rear of the said connection of the source at which the relay at the exit end of the section is ever opened by a car or train passing through the section, each signal being controlled by the relay at the exit end of the corresponding section and by the relay at the entrance end of the. section neXt in advance.

ln testimony whereof I aflix my signature in presence of two witnesses.

HERBERT A. WALLACE.

Witnesses M. S. KIRKLAND, Gr. A. GAUGHAN.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents, Washington, ID. C. 

